Heat transfer apparatus



July 19, 1960 B. L MCDERMOTT HEAT TRANSFER APPARATUS 4 vsheets-sheet 1vFiled Feb. ll, 1957 f||||||llll| July 19, 1960 B. l.. McDERMo-r'r HEATTRANSFER APPARATUS 4 Sheets-Sheet 2 Filed Feb. 11, 1957 July 19, 1960 B.L. MoDERMoTT 2,945,627

HEAT TRANSFER APPARATUS Filed Feb. l11, 1957 4 sheets-sheer s ATTORNEYJuly 19, 1950 B. L. MCDERMOTT l 2,945,627

' HEAT TRANSFER APPARATUS Filed Feb. 11, 195'? I fa:

4 Sheets-Sheet 4 74 u] mvENTOR BY l A 1'1 ORNEY United States Patent'Odice 2,945,627 :Patented JulyA 19, 1960 HEAT TRANSFER APPARATUSBeniamin L. McDermott, 1612 Fargo, Los Angeles, Calif. Filed Feb. 11,1957, ser. No. 639,340

7 Claims. (Cl. 239-225) This invention relates to a heattransferapparatus of the type commonly known as evaporative condensersemployed in the cooling of heaters particularly in refrigerationsystems.

Conventional apparatus of the above character commonly embody anarrangement of metallic cooling tubes `for conducting gases to becooled, together with a means whereby Water and air are directed overthe surfaces of tubes in cont-act therewith to effect absorption of heatconducted through and radiating from the tubes `from the warm or hotgases :dowing therethrough and whereby the gases will be reduced intemperature to a pointat or slightly below surrounding air temperature`and whereby such cooling action may cause the gas to condense intoliquid within the tubes.

. The eiciency of such apparatus in effecting heat trans- `fer isprimarily determined by three factors, namely:

(l) .The -amount of tubing surface available `for heat transfer, itssurface condition -and the capacityof the tubing;

(2) YThe amount and temperature of the water to which .the tubingsurface is subject and the duration and extent of contact of the waterwith such surface; and.

(3) The temperature of the air and the volume and rate of. flow thereof.v

. The primary object of the invention is` to provide a construction andarrangement in a heat transfer apparatus of the evaporative condensertype whereby. the several above recited factors may be developed toattain a maximum or at least highly efficient contribution in effectingheat transfer, and wherein the several components Aareso constructed andcorrelated as to insure a high ratio of heat transfer relative to costsof operation and maintenance.

Another object is to provide mechanismwhereby water and air may bedirected onto yan assemblage-of cooling tubes by a fan, pump and movingsprayer actuated collectively by ra single motor driven shaft.

Another object is to provide a water circulating system wherein wateris-pumped from a basin and sprayed onto the tubing Iassemblage within laconiining housing and then returned to the basin for recirculation, andin which heat absorbed by the water will be transmitted to abody of airllowing through the apparatus counter to the sprayed water, so as topermit protracted circulation of a charge of water and in which meansare provided forautomatically replenishing the charge in vcompensationfor loss by evaporation.

Another object is to provide an arrangement in the vwater pumpingmechanism whereby the use of packing spraying element land mode of.operation thereof together withV an arrangement of the gas conductingtubing where by cooling water will be thoroughly distributed throughoutthe outer surfaces of the tubing and under forceable .2 y impact such asto minimize the taccui'nulation of lime deposits on the tubing and towhich arrangement is such that the water will be directed throughout thelength of the tubing at a uniform temperature so 'as to materiallyaugment heat transfer in comparison with apparatus wherein the water iscaused to progressively flow from one heat radiating section of tubingto another such that the temperature of the Water is increased to va.point Where the diiference in rtemperature between the water and gas inportions of the tubing is so reduced as to minimize the heat exchange.

A further object is to provide an evaporative condenser embodying fewoperatingparts so constructed as to be readily assembled and subject tolittle wear so as to minimize repairs, which is simple in constructionand highly economical in operation, and which is adapted to be designedin various sizes and capacities tomeet various requirements.

With the foregoing objects in view, together with such other objects andadvantages yas may subsequently appear, the invention resides in theparts `and in the combination, construction and arrangement of partshereinafter defscribed'and claimed, and'illustrated by way of example inthe accompanying drawing, in which:

Fig. l isa side view of the apparatus with parts shown in section andparts shown in elevation;

Fig.' 2V is `an enlarged vdetail in section with parts shown in'elevation as 'seen on the line 2--2 of Figui illustrating the Waterspraying element;

Fig. 3 is a view in front elevation 'with Ia portion of the housingremoved;

Fig. 4 is la detail depicting a fragmentary portion of the housing insectiongwith parts in elevation, the view being an enlargement of thehousing shown in section .at the left side of Figi with parts of the"apparatusk removed.

yFig. 5 is an enlarged detail in section as seen on the line 5--5'ofFig.2;

Fig. 6 is an enlarged detail in section taken von the line 6-6 ofFig. 2;Y.

Fig. 7 is a horizontal section and plan fas seen on the line 7%7 of Fig.3 on'a, reduced scale;

Fig. Brisa plan view of thesuper-structure ramegand Fig. 9 is -a view incross section and elevationtaken on the line 9 -9 of Fig. 8.

Referringto Vthe drawings more specifically A indicates `genn'ally thecasing of thejapparatus which embodies a rectangular main frame BformedV of angle iron members comprising upstanding corner posts a-aa--u.suitably spaced apart withtheir `channeled .inner faces presentedinwardly to. form guide. ways... The posts@ are united adjacenttheinlowerend portions by aligned angle iron rails b"bbfb arrangedinteriorlyof thepost s 'with byUaligned angle iron rails ic-c-,ce-..arrangedfexteriorly of the postswith theirY channeled sides .presentedoutwardly. and downwardly and .with their upper rmargins flush with theupper ends'of theposts.A

Mounted in and carried on the framejB isjarectangulfar housing Ccomprising sheet rnetalside walls oi-TnT-d-d unitedat their sidemarginsin lperpendicular relation tto .eac-h other producing cornerswhichare slidably engage able with Vthe posts a. The upper marginsofthefwalls d terminate on a common plane rand have outturn'ed, flangese which seat on the upper rails c whereby/the housing C Iis supported bythev frameA when positioned therein as particularly shown in Fig.' 4.v 1

The iower, ends yof are, side 'walls fd i'erlilinafe'fml 'fa `commonplanein upwardlyspaced relationltio ,thelQWer railsl b and have thereon,an inwardly. `extendiijlg.dori/.r1- wardly sloping rectangular 'ledgefhaving an psta'xiding ange g extending continuously along three of itsfour Vposed therebetween and aixed thereto.

inner margins with its fourth inner margin fitted with a downwardlyinclined apron h; the ledge f constituting a trough leading to dischargeover the apron h.

Mounted on the lower rails b is a basin D comprising a liat rectangularbottom wall and upstanding side walls j which latter terminate on acommon plane spaced a short distance below the ledge f. The apron hextends into the basin C a short distance below the upper edge of one ofits side walls.

Mounted on the upper end of the main frame B is a superstructure Eembodying a canopy supporting framework particularly shown in Figs. 8and 9 and which includes a rectangular frame F comprising side railseach of which is composed of a pair of parallel lengths of angle-ironmembers k-l disposed back to back with their channels extended upwardly.The frame F is dimensioned so that its outer member k will conform t theupper rails c fof the main frame B, while its inner member l is disposedso that the inner face of its upstanding web will extend on a verticalplane spaced slightly inward relative to the inner face of the adjacentside wall d of the housing C, for which purpose the members k-l areseparated by spacing strips m inter- The opposed inner members I--l ofthe side rails of the frame F have their horizontal webs cut away ordivided mediate their ends and aiiixed to the inner faces of theportions of the vertical webs of each of the members l-l extending alongsuch cut-away portions is a pair of upstandng spaced standards n-n whichproject both above and below the rails of the frame F. The upper ends ofthe standards n--n on opposed rails are affixed to and carry a pair ofhorizontally extending parallel bottom rails oo, while the lower ends ofthe standards n-n are affixed to and carry a pair of horizontallyextending parallel bottom rails r-r. Mounted on the top rails 0 0intermediate their ends is a base plate s for supporting an upendedelectric motor G the drive shaft t of which ends downwardly through theplate and is coupled to a vertically extending driving shaft H whichleads through a bearing u carried by the bottom rails r; the shaft Hbeing fitted with a spherical element v journalled in the bearing u and`affording a support for the depending shaft on which the latter isrevolvable. The shaft H and its mounting are arranged so that the shaftwill extend axially of the housing C, the shaft terminating adjacent thelower end of the housing C where it is connected by a coupling w to theupper end of the vertical impeller spindle x of a conventional sump pumpJ seated on the bottom of the pan D. The pump J has an inlet on itsunderside, a side outlet connected to a discharge tube y, and the usualbladed rotor z.

Seating on the margins of the horizontal webs of the inner member l ofthe frame F is a horizontally extending rectangular plate K having acentral opening L through which the shaft H extends, the plate Kcovering the upper end of the housing C except as to the opening L andbeing divided medially thereof into halves so as to permit mounting andremoval thereof from opposite sides of the shaft H.

IFixedly mounted on the shaft H above and adjacent the bearing u is afan M the multi-blades of which are disposed to travel within theopening L and are arranged to induct air from the housing C through theopening L and deliver it to discharge through an outlet N at one side ofa sheet metal canopy P carried onthe frame F and extending over the areabounded by the latter and overlying the frame work comprising thestandards n and top rails o.

Mounted within the housing C is a heat radiating unit Q here 'shown ascomprising a double bank-of lengths of metallic tubes 10 of verticallyextending serpentine formation with adjacent tubes of each bank thereofdisposed in spaced parallel side'by side relation to each other and withthe tubes of one bank slightly'otfset vertically and laterally relativeto the tubes of the other bank. Each length of tubing of each bankthereof preferably embodies several spaced apart horizontal leads 11connected by return bends 12 with the ends of the outermost leadsextending in opposite directions and connected with manifolds 13 towhich are connected pipes 14 leading exteriorly of the housing C to andfrom a gas circulating system, not shown, whereby gases t0 be cooled aredelivered through the unit Q in the usual manner.

A plurality of the serpentine tubes 10 extend on opposite sides of theshaft H to near opposed side walls d of the housing C while the returnbends of the tubes extend adjacent the other opposed side walls of thehousing, with the lowermost leads of the tubes spaced upwardly from thelower end of the housing while the uppermost leads are spaced well belowthe upper end of the housing.

In carrying out the invention the shaft H is equipped with a waterdistributor R which embodies a tubular cylinder 15 surrounding the shaftH in concentric spaced relation thereto, which cylinder is open at itslower end and is closed at its upper end by a reduction coupling 16which is fastened to the shaft H a short distance below the bearing u.The cylinder 15 is centered relative to the shaft H by diametricallyopposed axially aligned screws 17-17 which are threaded through thecylinder and abut opposite sides of the shaft H.

The cylinder 15 has a series of water discharge orifices 18 formed inthe wall thereof in a spiral arrangement leading along the length of`the cylinder whereby on rotation of the latter and the delivery ofwater thereto as will presently be described, jets of water will beprojected laterally of the cylinder in all directions and caused toimpinge on the tubes 10 of the heat radiating unit Q.

Aiiixed to the housing of the pump J and encompassing the lower portionof the shaft H and the upper portion of the pump spindle x is a nozzlepipe T the lower end of which is closed and the upper end of which isopen and terminates adjacent the open lower end of the cylinder 15 inspaced relation thereto forming a gap 19 between the adjacent ends ofthe pipe T and cylinder 15 which pipe and cylinder are of correspondingdiameters.

As a means for regulating the extent of the gap 19, a sleeve 20 isadjustably mounted on the upper end portion of the pipe T with its upperend presented toward the lower end of the cylinder 15, the sleeve beingfitted with a set screw 21 engageable with the pipe T whereby the sleevemay be securely held on the pipe in various adjusted positionslongitudinally of the pipe to vary the width of the gap 19 which servesas a relief water outlet to reduce pressure head in the cylinder 15 andalso to effect lateral projection of a sheet or film of cold wateracross the interior of the housing C above the lower lengths of the heatradiating tubes 10. The cylinder 15 has a series of inclined blades 19on the exterior of its lower end portion immediately above the gap 19which blades are arranged to deliect such of the water as may bedirected upwardly on its discharge from the gap 19 and divert ithorizontally. Delivery of water to the pipe T and cylinder 15 iseffected by the pump I through the discharge tube y which leads to andconnects with the pipe T adjacent the upper end of the latter.

The coupling w uniting the shaft H and spindle x being encompassed bythe pipe T, the latter is provided with a side opening 22 opposite thecoupling to give access thereto to permit connection and disconnectionof the shafts without detaching the pipe T from the pump I, the couplingw being of the slip-on type and secured to the shafts by set screws 23which may be actuated through the opening 22 to engage or disengage theshafts. A sleeve 24 formed of rubber or the like encompasses the pipe Tover the opening 22 to close the latter and is detachably held in placeon the pipe by clamps 25.

Water is supplied to the basin D through a pipe 26 fitted with adischarge valve 27 opening to the basin, which valve is automaticallycontrolled by a iioat 28 on geh-tess in arm connected to the valve in ausual manner, the oat being Iactuated by the fall and rise of waterlevel in the .basin to open and close the valve and thereby maintain asubstantially uniform volume of water in the basin thus compensating forloss of water as is occasioned by evaporation. The float 28 is arrangedbeneath the ledge f rearward of the apron h to shield it against directimpact of water flowing from the housing C into the basin D. The basin Dis equipped with an upstanding drain pipe 29 leading to a suitable pointof discharge for preventing accidental overflow of the basin.

The pump J is submerged in the water contained in the basin D with itsimpeller spindle x leading upwardly with a sliding lit through a sleevex in the hub z on the pump housing to which the pipe T is connected,which sleeve constitutes a tubular bearing for the spindle x as well asfor the shaft H since -the-latter is rigidly connected to the spindle xin continuation thereof. 'Ihe bearing thus `formed is submerged in watercontained in the pipe T whereby packing of the spindle x in its bearingand consequent friction is obviated as well as oil lubrication of thebearing rendered unnecessary since water in the bearing will affordadequate protection against excessive wear. Any leakage of water throughthe bearing as may occur. will be unobjectionable since the leakage willbe maintained in the water circulating system thereby causing no damageas might occur if it were outside the system.

Mounted in the upper portion of the housing C and extending thereacrossadjacent the underside of the top plate K is a vapor collecting andcondensing screen U comprising a pair of parallel horizontally extendingpanels each of which comprises a rectangular frame 30 fitted with aseries of inclined closely spaced sheet metal louvers 31 having inturnedupper margins 32, the louvered panels being positioned with the louverstherein oppositely in' clined relative to each other to form angularpassages between adjacent louvers. The frames 30 are seated on arectangular sill 33 supported on hangers 34 demountably attached toopposed side walls d of the housing C by screws 35.

By mounting the blower fan M, water distributor R and pump I on a singleshaft these elements are c01- lectively operated directly from a singlesource of power, and by suspending the actuating shaft H from a singleoverhead bearing u as herein set forth, power consuming friction due toa plurality of bearings is eliminated thereby affording economy ofoperation of the apparatus.

In the operation of the invention hot gases to be cooled and condensedare caused to flow through the tubes 10, water is supplied in the basinD, and shaft H is rotated by the motor G. Rotation of the shaft H drivesthe pump I, water distributor R and fan M. Actuation of the pump Jdelivers water from the basin through the discharge tube y into the pipeT filling the latter and effecting discharge of water from the openupper end of the pipe T both laterally through the gap 19 and into andthrough the then rotating cylinder 15 from whence jets of water areejected through the orifices 13, the water thus being directly sprayedonto the elements of the heat radiating unit Q and against the sidewalls d of the housing C from whence a portion of the water rebounds andagain impacts on portions of the unit Q. The margins of some of theorifices 18 may be inclined upwardly from the interior of the cylinderso as to direct jets of water discharging therethrough at an upwardinclination. Subsequently the discharged water returns to the basin D, aportion of the water raining directly into the basin and another portionbeing caught by the ledge f and directed therefrom over the apron h intothe basin. The sprayed water absorbs heat from the elements of the unitQ.

During the above recited operation the fan M acts to induct air into thelower end of the housing C and upwardly through the latter to dischargethrough the opening L in the top plate K and through the outlet N in theYcanopy lP, the incomingar flowing inwardly over the margin of the basinD beneath the ledge f and moving upwardly through the falling rain ofwater in the housing C. The ascending column of air within the housing Cabsorbs heat .from the water being sprayed in the latter and effectscooling thereof.

Water vapors rising with the air column are collected and condensed bythe screen U and returned to the basin D together with the sprayedwater. l

VAs before stated the float controlled feed valve 27 will act tomaintain the water supply in the basin D at a substantially uniformlevel.

While a specific embodiment of the invention has been shown anddescribed, the invention is not limited to the exact details ofconstruction set forth, and the invention embraces such changes,modifications and equivalents of the parts and their formation andarrangement as come within the purview of the appended claims.

I claim:

l. In a water distributing mechanism for heat exchange apparatus thecombination of a vertically extending rotatable shaft, having a lowerend, a tubular cylinder encompassing said shaft in spaced relationthereto and aflxed thereon, said cylinder being closed at its upper endand having an open lower end spaced above the lower end of said shaftand having a series of discharge orifices spaced apart along its length;a rotary pump spaced below the lower Vend of said shaft having anupright impeller spindle connected to andY driven by said shaft, saidpump having an inlet and an outlet, a pipe encompassing said spindle inspaced relation thereto having a lower end connected to said pump andhaving an open upper end encompassing and spaced from the lower end ofsaid shaft and terminating in spaced relationto the open lo'wer end ofsaid cylinder; a sleeve bearing in said pump encompassing said spindleco-operating with the connection between said pump and the lower end ofsaid pipe to close the latter to said pump; and a tube leading from saidpump outlet to the interior of said pipe.

2. The structure called for in claim l together with a sleeve adjustablymounted on the upper end portion of said pipe having an upper endpresented toward the lower end of said cylinder, and means for holdingsaid sleeve in various adjusted positions longitudinally of sa-id pipeto vary the relation of its upper end to the open lower end of saidcylinder.

3. The structure called for in claim 1 together with a sleeve adjustablymounted on the upper end portion of said pipe having an upper endpresented toward the lower end of said cylinder, means for holding saidsleeve in various adjusted positions longitudinally of said pipe to varythe relation of its upper end to the open lower end of said cylinder,and a series of inclined deilecting blades on the exterior of saidcylinder adjacent the open lower end thereof.

4. In a heat exchange apparatus, a water distributing mechanismcomprising a vertically extending rotatable shaft, a tubular cylinderencompassing and affixed to said shaft open at its lower end and closedat its upper end, said cylinder having a series of discharge orificesalong the length thereof; a rotary pump having an upright impellerspindle connected to and driven by said shaft; a sleeve bearing in saidpump through which said spindle extends; a pipe encompassing saidspindle and the lower end of said shaft in circumferentially spacedrelation thereto, said pipe having its lower end connected to said pumparound said bearing and closed thereby and having its upper end openingto the lower end of said cylinder; and a discharge tube leading fromsaid pump and connecting with said pipe; the open end of said pipe beingspaced from the lower open end of said cylinder to form a discharge gapbetween said pipe and cylinder.

5. In a heat exchange apparatus, a water distributing mechanismcomprising a vertically extending rotatable shaft, a tubular cylinderencompassing and aliixed to said shaft open at its lower end and closedat its upper end, said cylinder having a series of discharge orificesalong the length thereof; a rotary pump having an upright impellerspindle connected to and driven by said shaft;

a sleeve bearing in said pump through which said spindle extends; a pipeencompassing said spindle and the lower able means on said pipe forvarying the extent of said gap.

6. In a heat exchange apparatus, a water distributing mechanismcomprising a vertically extending rotatable shaft, a tubular cylinderencompassing and afxed to said shaft open at its lower end and closed atits upper end, said cylinder having a series of discharge orifices alongthe length thereof; a rotary pump having an upright impeller spindleconnected to andl driven by said shaft; a sleeve bearing in said pumpthrough which said spindle extends; a pipe encompassing said spindle andthe lower end of said shaft in circumferentially spaced relation theretosaid pipe having its lower end connected to said pump around saidbearing and closed thereby and having its upper end opening to the lowerend of said cylinder; a discharge tube leading from said pump andconnecting with said pipe the open end of said pipe being spaced fromthe lower open end of said cylinder to form a discharge gap between saidpipe and cylinder,

and detlector blades projecting laterally from said cylinder adjacentsaid gap.

7. In a heat exchange apparatus, a water distributing mechanismcomprising a vertically extending rotatable shaft, a tubular cylinderencompassing and affixed to said shaft open at its lower end and closedat its upper end, said cylinder having a series of discharge orices Yalong the length thereof; a rotary pump having an upright impellerspindle connected to and driven by said shaft;

' a sleeve bearing in said pump through which said spindle extends; apipe encompassing said spindle and the lower end of said shaft incircumferentially spaced relation thereto said pipe having its lower endconnected to said pump around said bearing and closed thereby and havingits upper end opening to the lower end of said cylinder; a dischargetube leading from said pump and connecting with said pipe, theconnection between said shaft and spindle comprising a set screwcarrying slip-on coupling VVarranged within said pipe, and wherein thepipe has a side opposite said coupling to give access thereto; and meanson said pipe for covering said side opening adapted to be positioned toexpose said opening.

References Cited in the le of this 'patent UNITED STATES PATENTS2,117,411 Erbach May 17, 1938 2,570,247 Kals Oct. 9, 1951 2,602,002Schutt July 1, 1952 2,709,110 Schmidt May 24, 1955 2,720,085 Boyle Oct.11, 1955 2,752,124 Nofziger June 26, 1956 2,771,283 Eranosian Nov. 20,1956 2,780,306 Boyle et al Feb. 5, 1957 2,783,088 Butler Feb. 26, 19572,817,960 Lustwerk et al Dec. 31, 1957

